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XXXIV. A Monograph of Streptopus, with the Description of a new Genus 

 now first separated from it. By David Don, Esq., Libr. L.S., Prof. Bat. 

 King's Coll. Lond. 



Read December 3rd, 1839. 



\t HILE engaged in investigating the affinities of Disportirn, my attention 

 was naturally directed to the examination of various genera, either belonging 

 to Melanthaceoe, or to families nearly related to it, and among others to the 

 two genera which form the subject of the present paper. In my former com- 

 munication I have already adverted to the new genus, of which Streptopus 

 lanuginosus is the type, and I have also noticed the position which it occupies 

 in the series of natural affinities, and that the chain of connexion between 

 Melanthaceoe and Smilacece is rendered complete by means of it and Disporum. 

 The new genus in question agrees with Disporum in its perianthium, in its 

 binary ovula, and in its habit and inflorescence ; but it differs in the position 

 of its anthers, in its ovula being pendulous, and in its less deeply separated 

 styles. 



The genus Streptopus was first proposed by the elder Richard in Michaux's 

 Flora Boreali- Americana, and was intended to include not only the Uvularia 

 amplexifolia of Linnaeus, but two other plants therein described for the first 

 time, namely, .S. roseus and lanuginosus. The two last are exclusively con- 

 fined to North America, while the first is common to Europe and America. 



The characters of the genus consist in its hexaphyllous campanulate peri- 

 anthium, with the sepals deciduous, and furnished with a nectariferous furrow 

 at their base ; erect sagittate anthers, with short dilated filaments ; three 

 separate stigmata ; and in its baccate pericarpiuin with polyspermous cells. 

 These characters will be found united in S. amplexifoUus, which must be 

 considered as the type ; and a careful comparison of it with the other species 

 included by Richard clearly^ shows that lanuginosus must be removed from 

 the genus. The genus, as here proposed to be limited, will comprise S. am- 



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